Hide the Megadroughts

This is not a particularly nuanced or complex issue. What Field says the IPCC says is blantantly wrong, often 180 degrees wrong. It is one thing to disagree about scientific questions, but it is altogether different to fundamentally misrepresent an IPCC report to the US Congress.

Pielke noted in connection with droughts:

Field conveniently neglected in his testimony to mention that one place where droughts have gotten less frequent, less intense or shorter is … the United States.

Field was Co-Chair of the recent IPCC SREX report on Extremes, which reported this fact in unambiguous terms as follows: (p182) [added Aug 2]

In North America, there is medium confidence that there has been an overall slight tendency toward less dryness (wetting trend with more soil moisture and runoff; Table 3-2), although analyses for some subregions also indicate tendencies toward increasing dryness. This assessment is based on several lines of evidence, including simulations with different hydrological models as well as PDSI and CDD estimates (Alexander et al., 2006; Andreadis and Lettenmaier, 2006; van der Schrier et al., 2006a; Kunkel et al., 2008; Sheffield and Wood, 2008a; Dai, 2011). The most severe droughts in the 20th century have occurred in the 1930s and 1950s, where the 1930s Dust Bowl was most intense and the 1950s drought most persistent (Andreadis et al., 2005) in the United States, while in Mexico the 1950s and late 1990s were the driest periods. Recent regional trends toward more severe drought conditions were identified over southern and western Canada, Alaska, and Mexico, with subregional exceptions (Dai, 2011).

Field’s SREX report noted paleoclimate evidence for past megadroughts (which occurred in the US as well) – an important piece of evidence that Field did not disclose in his testimony. [added – Aug 2]

From a paleoclimate perspective recent droughts are not unprecedented, with severe ‘megadroughts’ reported in the paleoclimatic record for Europe, North America, and Australia (Jansen et al., 2007). Recent studies extend this observation to African and Indian droughts (Sinha et al., 2007; Shanahan et al., 2009): much more severe and longer droughts occurred in the past centuries with widespread ecological, political, and socioeconomic consequences. Overall, these studies confirm that in the last millennium several extreme droughts have occurred (Breda and Badeau, 2008; Kallis, 2008; Büntgen et al., 2010).

Tailoring of AR5?
The AR5 Zero Order Draft on paleoclimate stated, in language reminiscent of Soon and Baliunas, “multiple studies suggest that current drought and flood regimes are not unusual within the context of last 1000 years”. However, the First Order Draft was substantially changed to language apparently tailored to avoid a direct contradiction of alarmist narrative.

The occurrence and spatial extent of past megadroughts may be clustered over time following regime changes. There is evidence for more severe droughts during the LIA in South Asia, eastern Northwest China, and Southeast Asia, west Africa and parts of Europe [(Buckley, 2010; Sinha, 2007; Shao, 2010; Zheng, 2006; Zhang, 2008; Sinha, 2007; Sinha, 2007; Helama, 2009; Buntgen, 2011; Pauling, 2007; Cook, 2010 ; Russell, 2007; Shanahan, 2009)] compared to the predating MCA and the last century. In contrast, drought extent in North America, northern and central Europe, and East Africa were significantly greater during 900–1300 than during the LIA and the last century [(Cook, 2007; Cook, 2010; Herweijer, 2007; Helama, 2009; Luoto, 2010; Russell, 2007; Verschuren, 2000; Stager, 2005)]. Proxy information indicate, that intervals of severe drought in western Africa lasting for periods ranging from decades to centuries are characteristic of the monsoon and are linked to natural variations in Atlantic temperatures ([Shanahan et al., 2009]; see also Sections 5.5.2.1 and 5.6.2). Proxy reconstructions and model experiments suggest that variability in the tropical Pacific might partly account for the occurrence of megadroughts in North America with related teleconnections in all continents (Seager et al., 2008). A strengthening of the zonal SST gradient in the tropical Pacific via an enhancement of La Niña state and possibly warming of the Indian Ocean during periods of the MCA may have contributed to arid conditions in North America (Graham et al.; Seager et al., 2008), contrasting with wetter conditions in Asia (Graham et al., 2007). During the MCA, positive NAO conditions (see Section 5.5.5.3) and AMO phases may have favored wetter winter conditions in NW Europe and arid in NW Africa [(Graham, 2007; Esper, 2007; Touchan, 2008; Touchan, 2010)]. El Niño phases seem to have been more prominent during the LIA than the MCA, in coincidence with monsoon weakening Section 5.5.2.1) and drought occurrence in Asia (Buckley et al., 2010; Cook et al., 2010a),

…Overall, multiple studies suggest that current drought and flood regimes are not unusual within the context of last 1000 years [(e.g., Cook et al., 2010; Seager et al., 2008; Graham et al., 2010)].

Now here is the corresponding section of the First Order Draft:

5.4.2.2 Megadroughts and Floods
Paleo drought reconstructions provide estimations of the frequency, duration and severity of past dry periods. Megadroughts are comparable in intensity to present drought events but with durations longer than several years to a decade (e.g., Seager et al., 2009).

Figure 5.12 shows regional PDSI (Palmer Drought Severity Index) values reconstructed using tree rings in North America and Monsoon Asia (Cook et al., 2004; Cook et al., 2010), duration of droughts, their severity, and their frequency. Proxy information indicates that intervals lasting from decades to centuries of more frequent severe drought in western Africa are characteristic of the monsoon and appear to be linked to variations in Atlantic temperatures (Shanahan et al., 2009; see also Section 5.6). Proxy reconstructions and model experiments suggest that strengthening of the zonal SST gradient in the tropical Pacific or more severe La Niña conditions, and possibly warming of the Indian Ocean, during periods of the MCA may have contributed to arid conditions in North America (Graham et al., 2011; Graham et al., 2007; Seager et al., 2008), contrasting with wetter conditions in Asia (Buckley et al., 2010; Graham et al., 2011; Graham et al., 2007), although direct evidence of SST variability and ENSO state is more equivocal (Emile-Geay et al., in press). During the MCA, positive NAO conditions (see Section 5.4.3.2) and AMO phases may have favored wetter winter conditions in NW Europe and arid in NW Africa (Esper et al., 2007b; Graham et al., 2007) although Touchan et al (2011) do not find evidence of overall changes in mean drought conditions in northwestern Africa. The transition from the MCA to the LIA appears to coincide with monsoon weakening and megadrought occurrence in Asia (Buckley et al., 2010; Cook et al., 2010), while in North America an apparent shift toward overall wetter conditions occurs in the middle of the 14th century (Cook et al., 2004).

Note carefully that the First Order Draft suppressed any explicit mention of historical megadroughts exceeding those in the modern instrumental record (attested in the Zero Draft by a substantial literature. In my opinion, the language in the Zero Order Draft was a better assessment of paleoclimate information.

What was the justification for IPCC authors removing this important information from paleoclimate? It appears to me that the information was deleted because it was inconsistent with alarmist narrative on droughts and not for a valid reason.

To borrow a phrase from Phil Jones, one might say that the evasive language of the First Order Draft was a trick to hide the megadroughts.

Postscript: In Field’s day job, he does statistical analyses of crop yields. His main claim to fame is arguing that increased temperatures have reduced crop yields. Given the astronomical increase in crop yields during the 20th century concurrent with temperature increases and many confounding factors, this is an uphill job. Field’s frequent coauthor, David Lobell, attracted attention with an article in Science last year, expanding on this point. I looked briefly at that article (but did not post on it.) I was amused that it used the CRU-TS data set excoriated by Harry-Readme. (As I recall, the harry readme was explained away on the basis that no one used the CRU-TS data set, a memo that Field and coauthors do not appear to have received.)

My bad, I was thinking of Prof. Field’s other drought claim. From Roger Pielke’s article:

2. On US droughts:
Field:

“The report identified some areas where droughts have become longer and more intense (including southern Europe and West Africa), but others where droughts have become less frequent, less intense, or shorter.”

What the IPCC actually said:

“… in some regions droughts have become less frequent, less intense, or shorter, for example, central North America …”

Field conveniently neglected in his testimony to mention that one place where droughts have gotten less frequent, less intense or shorter is … the United States. Why did he fail to mention this region, surely of interest to US Senators, but did include Europe and West Africa?

We now return you to your regularly scheduled megadroughts, with my apologies.

Your graph – historical or pre-historical or not – shows a similar max-min cycle. Temperature and other data I’ve seen shows pre-historical max-mins much higher than today, but these are explained away as data certainty prolems. Is it possible that, in fact, pre-1950 (and far further back), the cycle variance was much greater than today, that we have been living in a relatively STABLE time, the departure from which is causing so much consternation?

The assumption is that stability and a low variation is normal. All data is smoothed to reflect this. But if this base assumption is false, long-term running means distort prior realities. This goes for solar TSI, sea-level changes, everything.

I’m a geologist. I see constant cycles in the rock records. Geologists have said it is as if the Earth were “breathing”, in-out, in-out. If we are coming from an “in” period,the “out” will be abnormal.

How do we know that the larger apparent variations of the past are uncertainties, and not real?

To borrow a phrase from Phil Jones, one might say that the evasive language of the First Order Draft was a trick to hide the megadroughts

Well, according to my reading of AR5_Writing Teams_updated_26 Sept 2011.pdf, one of the Lead Authors of WG1 Ch5 is none other than Tim Osborn. Kinda gives a whole new meaning to ‘many a truth is said in jest’, eh?!

Never let it be said
That the team is not nimble
When it comes to hiding
Peas under a thimble

On a somewhat more serious, and perhaps disappointing, note, Valerie Masson-Delmotte (whose response to you had previously been “encouraging”, as I recall) is one of the two CLA’s of this Chapter.

But all in all I find it astounding that the IPCC do not seem to have learned any lessons from the experience of the last two or three years.

“From a paleoclimate perspective recent droughts are not unprecedented,
with severe ‘megadroughts’ reported in the paleoclimatic record for
Europe, North America, and Australia (Jansen et al., 2007). Recent studies
extend this observation to African and Indian droughts (Sinha et al.,
2007; Shanahan et al., 2009): much more severe and longer droughts
occurred in the past centuries with widespread ecological, political, and
socioeconomic consequences. Overall, these studies confirm that in the
last millennium several extreme droughts have occurred (Breda and
Badeau, 2008; Kallis, 2008; Büntgen et al., 2010).”

This is merely from a U. of Arizona press release in 2007 describing a study, but it refers to a southwestern “megadrought” in the 12 century that far exceeded anything in the past 50 or 100 years (of course there is a quote from one of the co-authors suggesting we can expect such megadroughts from climate change in the future — “an analogue for what we could expect in a warmer world” was the expression):

An epic drought during the mid-1100s dwarfs any drought previously documented for a region that includes areas of Arizona, Colorado, New Mexico, Utah and Wyoming.

The six-decade-long drought was remarkable for the absence of very wet years. At the core of the drought was a period of 25 years in which Colorado River flow averaged 15 percent below normal….

….

….”The biggest drought we find in the entire record was in the mid-1100s,” said team leader David M. Meko, an associate research professor at UA’s Laboratory of Tree-Ring Research. “I was surprised that the drought was as deep and as long as it was.

Colorado River flow was below normal for 13 consecutive years in one interval of the megadrought, which spanned 1118 to 1179.

Meko contrasted that with the last 100 years, during which tree-ring reconstructed flows for the upper basin show a maximum of five consecutive years of below-normal flows….

In criticising Field, this post quotes at length from the AR5 on megadroughts. We read:“The Zero Order Draft on paleoclimate contained findings that directly contradicted Field’s testimony, stating, in language reminiscent of Soon and Baliunas, “multiple studies suggest that current drought and flood regimes are not unusual within the context of last 1000 years”.”

What it doesn’t do is quote, or even link, what Field said. He’s talking about the SREX report:

“Based on the analysis of historical records since 1950, the report identified trends of increasing extreme hot temperatures, intense precipitation, and extreme high sea levels. It concluded that there is evidence that human-caused climate change played a role in these changes in extremes. The report identified some areas where droughts have become longer and more intense (including southern Europe and West Africa), but others where droughts have become less frequent, less intense, or shorter.”

> [Field’s testimony does not reference] the last 1000 years. Since 1950. No reference to megadroughts.

I followed Nick’s link to the PDF of Fields’ Aug. 1 Congressional testimony (3 pages of text, plus figures). Nick is correct: Fields does not discuss the pre-instrumental period or its record of droughts and other events.

“Across the world, many records reveal that the 20th century is probably not the warmest nor a uniquely extreme climatic period of the last millennium.”

and from the paper:

“Barnett et al. (1999) has pointed out that it is impossible to use available instrumental records to provide estimates for the multi-decadal and century-long type of natural climatic variations, owing to the specific period and short duration of instrumental records.”

If we can assume that the occurrence of “extremeness” as the proponents would depict, as still within the statistical error bounds, than the next question is whether the statement is deliberate or not deliberate. If it is not deliberate than one would assume that there is in the jurisprudential sense an “honest” mistake. If it is otherwise, that is it is a deliberate statement that still falls within the statistical error boundaries, than “extremeness” becomes an adjective that is by definition outside the principle of logic.

As noted by Nick Stokes and AMac, Field’s testimony was limited to post-1950 data, so this post should be modified. I think all that needs to be changed is this:

The Zero Order Draft on paleoclimate contained findings that directly contradicted Field’s testimony,

Rather than say the ZOD “directly contradicted” his testimony, this should say something about how his testimony would be greatly weakened by what the ZOD said, and his failure to discuss paleoclimatic information is tellingly mirrored by the IPCC’s suppression. The thrust of the post would remain unchanged, but Fields would come across somewhat better.

morebrocato, there are times it could be an appropriate boundary, such as if one was studying a data set that only existed since 1950. Even then it would be important to highlight the limits of the discussion.

In this case, Fields was discussing a report which had quite a bit to say about paleoclimatic records. His decision to omit that topic from his testimony is, at best, misleading.

You know darn right well that a discussion of droughts, warmth, and anything associated with it that does NOT include the 1930s is disengenuous. There is no way to be able to come out and declare that you are properly delivering the prevailing climate understanding and trending by starting post-1950 in these weather categories.

To trust a communicator, you have to be confident that he will tell you all the reasons why you shouldn’t believe his message as well as reasons why.

Nick regularly defends real_climate_scientists on the basis that a given statement, even if it didn’t disclose highly relevant information, wasn’t actually a lie. For example, Stokes says:

Field wasn’t assessing trends. He was simply reporting to the Senate what SREX said about AGW and droughts.

Well, he wasn’t “simply reporting” what it said. He selected points of emphasis in his testimony, omitting mention of past megadroughts, even in the US, and the observed trend in the US of “less” dryness over the 20th century.

If Field wishes to do more than preach to the base, if he wants to actually change someone’s position, he’d be better off presenting the evidence against his position himself and directly confronting the evidence, rather than the too-common climate science practice of picking only those points that he believes to be favorable to an alarmist narrative.

“To trust a communicator, you have to be confident that he will tell you all the reasons why you shouldn’t believe his message as well as reasons why.

Nick regularly defends real_climate_scientists on the basis that a given statement, even if it didn’t disclose highly relevant information, wasn’t actually a lie.”

These two paragraphs contain the essence of the lessons to be learned from interpretations of published and reviewed accounts for policy purposes. What is often transparently clear is when the interpretation takes on an advocacy view and like the case of the good adversarial trial lawyer you should expect to see mainly one side of the evidence. I find Nick Stoke’s reactions in these matters a rather good indicator of where a person with an advocacy end result in mind – be that person a scientist or layperson – could rationalize a one-sided interpretation. I think if Nick had not shown up at these blogs we would have had to invent him.

The lesson learned in my mind is that the interested parties to any of these debates must become very much involved in reading and understanding, as best they can, the original literature and judging for themselves how well the evidence holds up to analysis and if nothing else get a reasonable feel for the uncertainty of the evidence presented.

He’s not selecting points of emphasis on droughts. He just said to the Senate (quoting SREX) that some places were getting droughtier, some less so. What do you think he’s trying to emphasise?

Nor does the “unambiguous” para from SREX that you now quote appear to push any barrow. It just starts:“In North America, there is medium confidence that there has been an overall slight tendency toward less dryness…”

Hard to see how anyone could get stirred about that. And yes, SREX does go on to mention a few past US droughts. It’s a report on extreme events, after all. I can’t see anything that you’ve quoted which would be seen in a different light following a discussion about paleo megadroughts.

Field had limited time before the Senate. He devoted just one “some up, some down” sentence to droughts, explicitly talking about post 1950. I can see no reason why he should be expected to divert into a discussion of prehistoric megadroughts.

If I willfully withheld information that the Nuclear Regulatory Commission might reasonably need to make a decision, I would be put in jail. If I did it by mistake, then my employer would merely be subject to a potential fine.

“Actually it is still a lie. Leaving out relevant information which you know will distort the picture is a lie by omission.”

OK Carrick, spell it out. What’s the lie? He wanted to say that since 1950 some places have been more subject to drought, some less. A fairly unsurprising statement, I would have thought. But no, he’s lying unless he:

1. Gives an account of prehistoric megadroughts in the US?
2. Talks about volcanoes?
3. Explains about the PDO?

“In so doing, he chose to not mention what the report said about the U.S.”
He devoted one sentence in total to droughts. Time addressing the Senate is limited. So what’s your brief version of the mention he should have made about what the report said about the U.S.? Specifically, U.S.?

Since he mentioned by name specific areas that show an increase, he then should have mentioned areas of particular interest that show no increase or a decrease, especially including bits that concern the USA.

He finds “southern Europe and West Africa” to be worthy of mention, after all.

re Stokes Aug 2 8:33 AM: Congress typically wants high level and intellectually honest assessments when they hear from experts. Or, at least their constituents want that. If they only needed some verbatim report, they don’t need Field to read it to them. They want answers. Specifically, they want to know if CAGW is going to cause unprecendented droughts in the U.S.

Field is only one of many scientists in the US who raise the issue of ‘megadroughts’ to policy makers as an apparently urgent call to enact ghg regulation. Yet in fact megadroughts that are well known to have occurred naturally in the past, are evidence against any certainty regarding CAGW and droughts causality. Scientists reporting to Congress have an obligation to bring these uncertainties front and center.

I observed a very similar spectacle recently in New Mexico at an annual New Mexico Water Dialogue meeting. Professors Craig Allen a USGS ecologist, and David Gutzler, a climatologist lectured to the assembled water resource policy and technical community that such megadroughts were surely in store for our state unless something was done to reduce or eliminate ghgs: (see cover page of link below) http://www.nmwaterdialogue.org/sitebuildercontent/sitebuilderfiles/spring2012.pdf

I followed up with an essay that the Water Dialogue reluctantly linked to. It might be of interest to any reader of this megadrought topic. Getting them to link to it is probably an interesting story in itself, but all I know is that their Board was sharply divided on whether to even aknowledge any legitimate skepticism on this issue.http://www.abeqas.com/WallaceNewMexicoWaterDialogueCommentary.html

Bob Tisdale has shown that PDO is largely inversely related to temperatures in the North Pacific in the observational record over decadal timescales. That recon, if correct, might imply a warm North Pacific (especially in the western part) during the MWP, although given PDO’s relationship with ENSO it presumably would also mean a cool Equatorial Pacific during the MWP. Well, assuming temperature patterns remain consistent-but if they don’t, then one can’t quite call that recon “PDO” since PDO is a pattern…

I would have thought a climate auditor would have noted that every time Field accurately quotes the IPCC 2012 report about hazards, Pielke Jr misrepresents it as a claim about financial losses. There is an important distinction between the two, one which, given his area of expertise, Pielke Jnr cannot have been unaware of. In the most absurd case, Field accurately reports the IPCC 2012 report on extreme precipitation events, and Pielke Jnr purports that it is a misrepresentation because of something that report said about flood losses. Put simply the distinction between precipitation and floods is not a hard one to make – and a fundamental one for Pielke Jnr’s area of expertise. Further, the distinction between flood events and losses due to flood events is again not difficult to make. Pielke Jnr, despite being well versed in these distinctions, fails to make them at every point, and treats his own failure to make these distinctions as proof of Field’s perfidy.

Of course, it is not actually proof of Field’s perfidy, who did not misrepresent the contents of the report. Rather, it is proof that Pielke Jnr is prepared to quote out of context, and pull a snow job in order to denigrate those he considers political opponents.

McIntyre adds to the fun by making it also proof of the one sided nature of his “climate auditing”.

As the US copes with the aftermath of last year’s record-breaking series of 14 billion-dollar climate-related disasters and this year’s massive wildfires and storms, it is critical to understand that the link between climate change and the kinds of extremes that lead to disasters is clear.

and from page 4:

The US experienced 14 billion-dollar disasters in 2011, a record that far surpasses the previous maximum of 9 (NOAA 2012a). The 2011 disasters included a blizzard, tornadoes, floods, severe weather, a hurricane, a tropical storm, drought and heat wave, and wildfires.

It looks to me that the financial theme was set by Field right from the start. You expected that this aspect should have been ignored?

Field wasn’t summarizing the report. He was advocating a particular viewpoint to Congress using selectively chosen supporting evidence and couching it in a specious financial context in order to attract their attention. The failure seems to be your inability to comprehend this.

No, Field was not summarizing the report. He was summarizing chapter three of the report. There was no reason for him to pretend to expertise in economic matters, and he did not do so.

The simple fact is that hazards are increasing, as the report says. With increased hazards there will be an increase in disasters unless better construction standards, early warning systems, flood mitigation systems etc are deployed to counter the increase. Consequently, an increase in hazards has an inevitable financial cost either in disasters suffered, or in increased costs in preventing them. Field, not being an economist, does not speak to whether hazard mitigating strategies will be cost effective or not. He warns that a policy to deal with increase hazards will be necessary, but does not advise on which policy that should be:

“In summary, there is no doubt that climate has changed and that changes will continue in the
future, with human emissions of heat-trapping gases playing a major role. There is also no doubt that a
changing climate changes the risk of extremes, including extremes that can lead to disaster. It is only by
understanding those risks in the most clear-headed, objective way possible that we, as a nation, can 5
make good decisions about the challenges of protecting and enhancing our natural legacy, our economy,
and our people.”

Pielke, and apparently McIntyre and you don’t like that message, so Pielke has erected, and you and McIntyre have accepted, a strawman by the grand old tradition of out of context quotation.

You just don’t get it. Pielke was replying quite effectively to what Fields was telling the Congressional committee. You can spin it any way you like, but that is what one should do when someone that you admit has no expertise in economic matters raises the issue in the very first paragraph of his presentation. Your ramblings about cost effectiveness are a straw man with zero relevance to the situation. The financial references were intended to get the politicians’ attention.

The simple fact is that there is little viable evidence that “hazards are increasing”. Your quote from the document is nonsense and non-science. It is what could be termed the Trenberth Dictum: We know that CAGW is happening as we have predicted so it must be undeniable that everything that occurs in this world must be affected negatively by it (even though after all this time we really don’t have genuine evidence to show this)>. The fact that someone has repeated the same thing a report is not evidence of anything.

It is not that I “didn’t like” Field’s message. It was that I recognized it as pure unsupported propaganda intended to influence the politicians.

Roman, if Pielke had written a blog saying that Field had testified x, but the more relevant fact is y I would not have a problem with what he wrote. I would disagree about the relative significance, but it is his and my perogative to disagree if we desire. But what Pielke did was charge Field with misrepresenting IPCC 2012. As Field did not do that, Pielke had to resort to quoting out of context, and blurring the distinction between hazards and losses from disasters. It is like charging somebody with misrepresenting Newton’s laws of motion because they do not quote from sections of a report discussing the costs of the US space program.

I note, however, from your final comment there is no further point in discussing this with you. I actually went through Field’s testimony and the report, and everything Field said was also said in the report. The most that can be said about him is that he discussed the facts regarding hazards but not the facts regarding losses from disasters. You may think, as does Pielke, that the only politically important fact is that it is not yet statistically certain that the increased frequency of certain types of hazards predicted, and observed with a warming climate, has caused increased losses. That does not make it propaganda to state correctly that the hazards have increased. If you regard stating facts directly drawn from the report, and relevant to policy making, whether that policy is to increase water storage for flood and drought mitigation, or to reduce greenhouse emissions to mitigate further warming, or what ever as “unsupported propaganda” you are clearly not to be reasoned with.

If you disagree with Pielke, by all means, go discuss it with him. However, it is quite clear that he was dealing quite directly with the issues raised by Field in his testimony.

You may think, as does Pielke, that the only politically important fact is that it is not yet statistically certain that the increased frequency of certain types of hazards predicted, and observed with a warming climate, has caused increased losses.

If you know my background at all, you will understand that I am not impressed by or bound by the concept of “statistical certainty” since that has been in the core of my education and profession for well over 45 years. However, I can recognize when someone such as Trenberth tries to convince people of his beliefs by trying to reverse the role of the null hypothesis and making claims which clearly have no scientific backing. It is not “statistical certainty” that is needed, but the gathering and honest evaluation of the actual evidence for and against the claims that would put all these issues in the proper context. Without that, all you have is propaganda. Climate scientists need to recognize that.

Had Pielke wanted to deal directly with issues raised by Field, he would have agreed with Field that the report indicated an increased return frequency for certain natural hazards as a result of global warming; agreed also that there has been an increase in losses due to natural disasters, but argued that those increases are sufficiently explained by increasing populations, value of infrastructure, and a shift of populations to more vulnerable positions. Instead he accused him of misrepresenting the IPCC 2012 report. That constitutes an evasion of the issues – not a discussion of them. It is a resort to ad hominen in preference for arguing his case. The resort to ad hominen is made worse because he had to quote Field out of context, and misrepresent the IPCC 2012 report himself to do it.

I note that your reference to Trenberth is a red herring, deliberately deployed as such. The IPCC 2012 did not adopt Trenberth’s ” reverse standard of proof”, and nor do I. Nor is there any evidence suggesting that Field accepts it. So what we had from the IPCC 2012 was an “honest evaluation of the actual evidence”. Your appeal to your “well over 45 years” of statistical experience in lieu of actually examining Chapt 3 of the report and showing how Field misrepresented it shows the hollowness of your position. You deploy your authority and a rhetorical appeal for honest examination of evidence to avoid actually having to examine the evidence you find uncomfortable.

Had Pielke wanted to deal directly with issues raised by Field, he would have agreed with Field …

So you are a mind-reader too. Do you have other ESP skills as well? I would let Prof. Pielke answer for himself.

You don’t seem to understand that the reason that Trenberth tried to flip statistical science on its head was that there is no credible evidence that extreme weather has increased up to this point and no valid predictive evidence that it will automatically do so in the future. So it is not a red herring but an affirmation that even scientists who honestly study these things share a similar viewpoint. My statement about my statistical experience should tell you that I am not a beginner but that I am quite familiar with the application of statistical procedures and the interpretation of the results of such procedures. That experience includes consulting for research in most areas of university studies so it is not simply theoretical academic knowledge. Evaluating research analyses and offering constructive advice in a broad variety of disciplines was something I did on a regular basis.

Somehow your expectation that I would find this missing evidence hidden deep within Chapter 3 of a partisan summary report rather than within the original sources and their over-hyped press releases is a bit laughable.

Had Pielke wanted to deal directly with issues raised by Field, he would have agreed with Field that the report indicated an increased return frequency for certain natural hazards as a result of global warming;

That is what Pielke does believe, and stated in his blog. It is also what the IPCC said.

What Pielke objects to is the belief that the evidence is already present for increased natural hazards. Field says it is, and the IPCC says it isn’t. So Pielke rightly castigates Field for making stuff up.

Pielke is not a skeptic, despite what many alarmists claim. He just doesn’t like people making up evidence to suit their own personal agendas.

It is a resort to ad hominen in preference for arguing his case. The resort to ad hominen is made worse

You need to read up what “ad hominen” means. Pielke does not engage in anything remotely resembling that. Disagreeing with a person is not, repeat not, an ad hominen attack.

He believes Field is wrong, and backs up his belief with evidence. That you see that as a personal attack is a misreading of the situation.

Steve McIntyre, at 10:26 AM, the report does not mention a trend to less drought in the United States. That is Pielke Jnr’s language; and a deliberate attempt to obfusticate. What the report mentions is a reduced tendency to drought in central North America, a vague region which probably includes part of the contiguous US, but may not include all of it. Indeed, given the trend to increase drought duration and intensity in significant parts of the Western contigious US, treating the US as a single homogonous region in which drought has been reducing would have been to mislead Congress. So Field did not mislead congress, but Pielke Jnr has mislead you.

You wrote “What the report mentions is a reduced tendency to drought in central North America”, That’s funny. Hansen opened his 1988 US Congress climate speech with a projection of something pretty much the opposite”
They can’t both be right.

snarkmania, at the end of his congressional testimony in 1988, Hansen predicted increased drought for the South East and Mid West of the United States. He was wrong on that point, but has been shown to be correct on all other points which he raised. Now are you trying to build your case against AGW on the fact that a 1982 computer model which could only be run once per scenario due to the limited computer capacity available in 1988 (it was run on a 1960’s mainframe) had some errors? Are you really that desperate for straws to clutch at?

There’s so much low hanging fruit to discredit AGW, I can only point you to my original links at my first comment to maybe begin to address your concern.

With regard to your other point, you are wrong again, as was Hansen, multiple times at that 1988 Congressional testimony. In a presentation festooned with claims of 99% certainty, he predicted that the Great Lakes levels would have lowered by now. When he made this prediction, I believe he left the audience with a perception that he was speaking in linear terms and that this would be a significant event. However, I was just in Chicago and I looked for any indication of lowering of Lake Michigan. No luck. The water was splashing over the concrete breakers at Oak Street Beach on that rather nice day.

At that same 1988 Congressional hearing, Hansen predicted a sea level rise rate that, when one accounts for the passage of time, would now amount to over a foot of rise. Yet, the rough level of global sea level rise since then is about a fifth of that. The rate of rise over this period of time appears to be lower than the average sea level rise rate associated with past interglacials. When he made this prediction, I believe he left the audience with a perception that he was speaking in linear terms.

I tried to reply earlier but may have been snipped.. not sure why. Yet to not respond might imply I don’t disagree so I’m trying again. Hansen was wrong on many points he raised in that Congressional testimony. Among other additional alarmist predictions that never came true was a prediction of the lowering of the Great Lakes.

I encourage you to read Hansen’s testimony and reevaluate your assertion. Hansen was not “correct on all other points he raised”… I’ll give you one for free…

His words, falsified:
“We have considered cases ranging from business as usual, which is scenario A, to draconian emissions cuts, scenario C, which would totally eliminate net trace gas growth by year 2000. The main point to be made here is that the expected global warming is of the same magnitude as the observed warming.”

A final comment – as I understand your post, you are trying to point out the perfidy of those global warming alarmists in that they are suppressing evidence of megadroughts in warm periods (MWP), and only retaining evidence of megadroughts in cold periods (LIA) in a calculated attempt to spread undue concern about a prospective warming of the Earth’s climate. Is that correct? LMAO

Tom Curtis, the point of this post was expressed succinctly by SM but you have not addressed it:

“What was the justification for IPCC authors removing this important information from paleoclimate? It appears to me that the information was deleted because it was inconsistent with alarmist narrative on droughts and not for a valid reason.”

Instead of 3 comments to hyperventilate and obfuscate, you could have tried addressing the actual post. This is not the SkS site where you can get away with every kind of babble unchallenged.

Skiphil, Tom Curtis has no interest in resolving anything. It’s much better for him to toss out tons of misinformation and smears. It lets him reinforce his views of people he dislikes, share those views with “more evidence” and collect talking points.

If he had the slightest desire to resolve anything, he’d behave radically different.

Brandon:
You have to forgive Tom Curtis and his analysis. His knowledge of droughts etc in North America is very limited in scope and study.
He has become adept at thinking climate models have value, when emperical evidence shows how little value they have for humanity as presently programmed.

Skiphil, your quote of the main article expresses exactly the opinion that leaves me bemused and amused. If McIntyre’s supposition made any sense, the IPCC would have removed references to mega-droughts during cold periods (the LIA) and left references to the mega-droughts in warm periods (MWP). In fact they did the opposite. And now he has a whole page of “climate auditors” who cannot see that simple fact. Very revealing, and very amusing.

I don’t know why the references to MWP mega-droughts where removed. I don’t think they should have been. But whatever the reason, McIntyre has not stumbled across it, because the motive he suggests in explanation would require the opposite actions to those carried out to be satisfied.

Out of interest, can Steve McIntyre link us to a publicly accessible and IPCC authorized source for his quotes from the drafts, or is he publicly endorsing the violation of non-disclosure agreements as a general practice?

TerryMN, either McIntyre is a reviewer and has signed the NDA, or he has received this information from a reviewer who signed a NDA and then breached it. In either case, by publicly disclosing the information McIntyre endorses the disclosure. You cannot knowingly receive stolen goods and then pretend you object to theft. So, by publishing this material, if obtained by the breach of the NDA, McIntyre is tacitly endorsing the breach of NDAs.
Steve: I did not sign the NDA. If I wish to endorse something, I will. Please don’t put words in my mouth.

That is not the one you are quoting from. Where can we get that copy to see it for ourselves what is in the rest of the chapter? The one at Appell’s site, AR5-Ch5-FOD is just figures and explanations of figures. No text in there.

I did not sign the NDA. If I wish to endorse something, I will. Please don’t put words in my mouth.

Tom Curtis did not put words in your mouth. If you read his comment carefully you will notice that it includes the word “tacitly” in front of “endorsing”, which any literate person would take to mean that endorsment is existent, but not spoken.

More generally, it’s curious to see how many people endorse this release of the AR5 material, whether tacitly or explicitly, but many of the the very same folk are rabidly furious about Wikileaks-style revelations (and no, I’m not tacitly including SMcI in this category). Is it just me or is there a double standard here?

Steve: I haven’t commented on Wikileaks. Nor, to my recollection, have commenters at this blog taken particular umbrage at Wikileaks. There are salient differences between the two situations which will appear relevant to some people but perhaps not to others.

But this is getting far afield. Do you think that IPCC was justified in removing its discussion of past paleodroughts? why do you think that they did it?

If McIntyre wants to know why the IPCC removed extensive discussion of North American droughts in the first order draft, he perhaps ought also to ask himself why they added North America to the figure on the severity duration and frequency of droughts (see fig 5.12). Compare this with the apparently equivalent figure 5.17 in the zero-th order draft, which includes data only from India, China, and the Tibetan Plateau.

He might also want to ask whey the first order draft mentions that:

“uring periods of the MCA may have contributed to arid conditions in North America”

and:

“The transition from the MCA to the LIA appears to coincide with monsoon weakening and megadrought occurrence in Asia (Buckley et al., 2010; Cook et al., 2010), while in North America an apparent shift toward overall wetter conditions occurs in the middle of the 14th century (Cook et al., 2004).”

(My emphasis)

In a section about mega-droughts, references to aridity are not difficult to interpret. Once the inclusion of figure 5.12 is allowed for, the result is that the first order draft has more information about NA megadroughts than the zeroth order draft, not less.

So, just possibly, the revisions are a result of a need to abbreviate the discussion; and taking advantage of extensive treatment of NA aridity in the figure to convey information previously conveyed in text.

Of course, that couldn’t be it, surely? After all, conspiracy theories are always far more plausible as explanations./sarc

“Do you think that IPCC was justified in removing its discussion of past paleodroughts?”

Hard to answer that without the complete text. But the FOD on David Appell’s site that you linked shows (p 95) the new figure 5.12 that they introduced. This shows an actual graph of the Palmer Drought Index for SW US from 800 CE to present. This gives more information than was available in the ZOD for this location. This seems to be “highly relevant information”.

“To trust a communicator, you have to be confident that he will tell you all the reasons why you shouldn’t believe his message as well as reasons why.”

@McIntyreNote carefully that the First Order Draft suppressed any explicit mention of historical megadroughts exceeding those in the modern instrumental record (attested in the Zero Draft by a substantial literature. In my opinion, the language in the Zero Order Draft was a better assessment of paleoclimate information.
What was the justification for IPCC authors removing this important information from paleoclimate? It appears to me that the information was deleted because it was inconsistent with alarmist narrative on droughts and not for a valid reason.

You just think of any reason that suits your prejudices, then judge them guilty. Same old, same old. Don’t you get tired of it.

Steve: I said that that’s how it appears to me. I’m prepared to change my mind if someone gives a good reason. So far, no one has.

McIntyre’s response here establishes his lack of bona fides. Both I and Nick Stokes have pointed to a very simple explanation of the changes, the totality of which result in more information about NA droughts in the first order draft, not less as McIntyre would have it. That explanation was that the section was edited for brevity, taking advantage of the additional information contained in figure 5.12 to do so. Editing for greater brevity is hardly an unusual requirement in academic papers or IPCC reports.

Rather than accept this simple hypothesis, however, McIntyre insists that his explanation that the alterations are the result of IPCC authors conspiring to remove relevant information is more plausible. He insists on this despite the fact that it would be to the advantage of “alarmists” to draw attention to mega-droughts associated with a warm period, not to hide them. And he insists on this despite the fact that, when figure 5.12 is included, we have more information about NA droughts, not less.

This refusal to accept a simple explanation, and to rely on a complicated explanation which is contradicted by the evidence instead shows all the hallmarks of motivated reasoning. That is, it shows that for McIntyre the conclusion comes first. He is only interested in this case to the extent that it reflects poorly on IPCC authors, and can be used to denigrate them. He therefore has no interest in any change in his opinion that would result in his not being able to conclude that the IPCC authors were up to skulldugery.

I think that your editing for brevity explanation would be a perfectly reasonable explanation taken in isolation. It could be supported by demonstrating how the other sections of the draft(s) were edited if this information were to become publicly available some time in the future.

The problem that someone like me has is that when this particular edit is taken in context with other edits in the past it gives the impression that the IPCC is skewing the available information to present a point of view that the current climate is not as good as it was and will continue to get worse, and that there is greater certainty in this global impression than is warranted.

An example of this is how the IPCC truncated the temperature proxy data when they started to diverge from the instrumental temperature record. This served to increase the certainty that the proxy trends were a fair representation of pre-instrumental temperatures.

Another example are the edits made in previous ARs where some reviewer suggestions were rejected out of hand while other reviewer suggestions incorporated into the narrative to strengthen the plot (as it were).

This is viewed after years of seeing the surface temperature trends being revised and after each revision seeing the past getting cooler and the present getting warmer. This of course was not the IPCC but part of the same community.

Would you be willing to consider that removing the referals to prehistorical megadroughts skews the story line in a way that makes future drought scenarios seem more alarming?

I think one related problem for this topic is the use of the term “megadrought”. It is not actually a scientific term in my opinion, although it has long ago found its way into peer reviewed literature. It is apparently intended to characterize a drought of unusual scope, presumably in terms of at least time and areal extent.

I wish researchers would write instead in terms of ‘xeric shifts’. Once a few generations have passed, an area might evolve from a grassland to a desert. If it’s now a desert, it’s not undergoing a drought anymore.

In the context of Pleistocene to modern day conditions, it’s entirely natural for SW US xeric shifts of colossal scope, growing and shrinking dramatically with roughly a 100,000 year periodicity. In that context, this term ‘megadrought’ seems to loose relevance.